That would depend on the said 26-year old's personality, strengths, weaknesses, dreams, and proclivities.
A. Physical development
- Take out 30-60 mins everyday for your health. Put on your shoes and start running. Or go to the gym and get pumped up. Or take up a sport. Or swimming. Or any other physical activity.
- Start eating healthy. It's fine to have that cheeseburger once a month or so, but seriously start eating healthy. You are young now, but 'this too shall pass'. Learn to cook for yourself. That way you become more self-reliant, eat healthier, and also save money on eating out.
- Learn self-defense: Take your pick from the multitude of martial art forms available. Be strong enough to defend yourself and others around you if the need arises.
B. Mental development
- Start a mentally stimulating hobby like solving puzzles, playing D&D, Chess, etc.
- Try and get rid of traits that hold you back - self doubt, risk aversion, validation from others, dwelling on past failures, being overly critical or defensive about yourself
C. Emotional development
- Learn to listen. To people who come to you for help. Learn to be a source of comfort for some, and advice for others. Learn to be compassionate, patient, and sympathetic.
- Learn to control your emotions, especially the negative ones: Try and control your anger issues. Make an effort to truly be happy for someone else's achievements; curb your jealousy.
D. Intellectual development
- Read. There is nothing that will help you more than reading. Read all types of books from young adult fiction to law. Read all authors from Dickens to Tzu. Read about contrasting viewpoints. Do not be afraid of coming across a convincing viewpoint that is totally antithetical to yours.
- Watch good movies. Movies aren't only about entertainment. Movies like District 9, The Truman Show, Good Will Hunting, 12 Angry Men, The Man from Earth will move you, will expose you to things that hadn't occurred to you yet, and will leave you pondering. Same goes for shows like The Wire, Band of Brothers.
- Talk: Talk to people who share similar interests as you. You will find that what you know about the subjects you love is too little. Talk to people with starkly different interests. You will find that the number of topics you know about is too little.
E. Social development
- Start giving back: Participate in community activities. Volunteer at a orphanage or an old-age home on weekends. Initiate a cleanliness drive in your locality.
- Join a club: A book club, debate club, or anything that interests you. Meet more people outside your friend circle.
- Go to pubs on karaoke night: Sing your heart out. Get rid of that crippling social anxiety. Learn to accept yourself and be comfortable around others.
- Learn to hold a conversation: Know what to ask, and how to keep the conversation going. Make the conversation a two-way exchange of information. Reading will help here because if you ask someone what they do in their free time and they say they like to read and you ask about their favorite author and they say it is James Joyce and you have read Dubliners, you can easily get the conversation to last for hours.
- Travel: With friends and alone. Visit far off lands, learn to make your own itinerary, handle your trip finances, plan and make bookings. Talk to the natives, learn about their culture, make some memories, blog about it. In the process you will learn, experience, imbibe, and pass on your learnings to others.
Finally, a list of things everyone should know about by the age of 20.
A. Survival and self-sufficiency
- Cooking
Face it, this should be taught in school. If you can't cook, you are dependent on others - your maid, your spouse, your local restaurants. What if it is late night and you are alone? Where will you be when hunger strikes? (:P). Stop thriving on easy-to-eat food.
(Get started , Website, Android app)- Budgeting and managing your expenses
- Basic survival skills
Imagine you are in an accident or a crash. Your chances of survival will solely depend on how well you can analyze the situation and use everything at your disposal to help you live and get out.
What you should know?
- Knowledge of plants and animal - edible, poisonous
- Knowledge of the major ecological spheres - forests, oceans, deserts, snowy mountains.
- How to conserve water
- How to build a shelter
- How to build some basic weapons
- A good signalling mechanism
- How to avoid predators
(All the above and more)
- Self-defense
The world can be a nasty place sometime. Know how to protect yourself and your loved ones if ever the need arises. (A good starting point)
Enroll yourself in a self-defense class. Have some basic training in martial art form. Build up your strength and agility.- Learn how to jump-start a car
- How to set up a camp
- How to make a fire without matches
- Emergency skills
B. Professional career
- Know how to build a good resume (Resume tips 1, Resume tips 2,Resume tips 3)
- How to apply for jobs and increase your chances of selection (Reading)
- How to make a good first impression (Reading)
- How to make good connections at work (Reading)
- Have a secondary marketable skill
What if you were an investment banker and suddenly found yourself without a job after the 2007 crisis?
Always have a backup. What else can you do except for trading and valuations? Can you code? Can you design something? Can you write? Can you work as a salesperson?
You should always have a secondary skill you can earn with. You might not be as adept at it, the industry might not be as well paying, but it will still save your skin in times of need.- Learn how to manage time and have a healthy work-life balance. (Reading)
- Learn coding.
Nothing can be more helpful in you day-to-day professional life than knowing a bit of computer sorcery. Know how to write the simplest of macros to automate mundane tasks, be efficient, remember all your To-dos. You have a pretty powerful machine at your disposal. Make it work. (Get started)
C. Personal lifeA person should be able to live alone - with no external contact or assistance. It's essential to take out time for family and friends, but equally critical to take out time for self.
- How to build stuff from scrap and basic household items (The best resource on the internet)
- How to stay fit without any equipment (100 no-equipment workouts)
- How to stay alone, yet entertained (74 things to do when you're bored and alone)
D. Social lifeYou might be an introvert who spends weekends in his living room, reading or surfing through channels. But contrary to point C above, man is after all a "social animal" and must know how to live among others.
- Know how to break the ice (Reading)
- Know how to strike up and hold an interesting conversation. Sometimes with complete strangers. Probably on topics you know nothing about. (Reading)
- Learn to listen. Listening may seem like a passive ability, but it isn't. There's a difference between hearing and listening and that is the level of engagement you have with the speaker. (Reading)
- Get people to like you (Reading)
- Learn to make cocktails and be the life of the party (Some easy recipes)
- Learn to make some easy-to-make snacks for when you are having people over (Some easy recipes)
- Public speaking. Join Toastmasters.
- Learn card games. May be poker? (Know your poker hands)
- Learn sign language (American Sign Language)
- Know how to remember people's names and faces. (Reading)
- Also, how to make proper introductions. To avoid awkward situations. (Reading)
- Or, how to tell a good story (Reading)
E. Misc